| Abstract Scope |
In this paper, the resistance coefficient of 90° bending pipe with 45° bending pipe and different ratio of curvature radius (R/D=1,2,3,4,5) was studied by experimental and numerical simulation methods, and the laws of pressure distribution, velocity vector, secondary flow and flow trajectory in bending pipe were analyzed, and the characteristics of flow field in bending pipe with different ratio of curvature radius to diameter were emphatically analyzed. The results show that the simulation results of RNG k-ε turbulence model agree well with the experimental results. Under the same Re, the larger the R/D, the smaller the local drag coefficient. When R/D increases the curvature in the range of 1-3, the local drag coefficient can be significantly reduced, and when R/D increases the curvature, the local drag is not significantly reduced. |